Quick change structure for multi-functional saws and quick change method

Abstract

The present invention relates to a quick change structure for multi-functional saws and a quick change method. The quick change structure has a head housing, an output shaft and a quick change device. On the quick change device, a quick change handle can be pulled to drive an eccentric block, a movable rod, a small cylindrical compression spring and a movable bracket in turn such that the second cylindrical pin at the lower part of the movable bracket moves downward in the guide slot of each one of locking pins, driving the locking pins to rotate around a third cylindrical pin to fold together. After a saw blade is placed, the locking pins will unfold when an upward force is applied, and then the locking pins lock the saw blade to realize quick change of the saw blade.

Description

[0001]This is a U.S. national stage application of PCT Application No. PCT / CN2018 / 082201 under 35 U.S.C. 371, filed Apr. 8, 2018 in Chinese, claiming priority of Chinese Application No. 201710671524.7, filed Aug. 8, 2017, all of which are hereby incorporated by reference.BACKGROUND OF THE INVENTIONTechnical Field[0002]The present invention belongs to the technical field of mechanical equipment and relates to a detachable structure for quick separation or assembling of a tool bit and a machine body of a replaceable tool bit type electrical tool, in particular to a quick change structure for multi-functional saws. The present invention also discloses a quick change method of the quick change structure for multi-functional saws.Description of Related Art[0003]The majority of multi-functional saws on the market employ a pressure plate and inner hexagon screws. The saw blade of a multi-functional saw is usually fastened or unfastened using a special tool or by manually rotating a fasteni...

AI Technical Summary

Benefits of technology

[0006]In order to overcome the above-mentioned defects, expand the application scope of products, and improve the operation feeling of products, the present invention provides a quick exchange structure for multi-functional saws, realizing quick change of saw blades.

[0012]The plastic fixed seat plays the role of bushing the two locking pins and connecting the cylindrical pins of the two locking pins to prevent the locking pins from swinging left and right; and the positioning ring plays the role of fixing the saw blade to prevent the saw blade from falling off during use.

[0013]Preferably, a deep groove ball bearing, a shift fork and a needle bearing are arranged between the head housing and the output shaft; the output shaft is divided into three segments, namely an upper segment, a middle segment, and a lower segment, as the outer diameter increases gradually; the deep groove ball bearing is arranged on the outer race of the upper segment of the output shaft; the shift fork is arranged on the outer race of the middle segment of the output shaft; and the needle bearing is arranged on the outer race of the lower segment of the output shaft. The deep groove ball bearing and the needle bearing play the role of preventing the output shaft from swinging during rotation, and the shift fork plays the role of controlling the rotation speed of the output shaft.

[0025]The technical scheme provided by the present invention, compared with the prior art, has the following beneficial effects:

[0026]The quick change structure for multi-functional saws of the present invention can achieve the objects of dismantling and changing the saw blade simply by pulling the quick change handle on the upper side of the head housing, without using other auxiliary tools. The operation is simple and fast.

Problems solved by technology

Without a locking safety structure, the saw blade of the multi-functional saw with such structure and replacement manner tends to become loose during rotation, bringing potential hazards to safety use.

Besides, the fastening and dismantling operations are complicated.

Sometimes, fastening fails, and sometimes, dismantling fails.

The hexagon wrench is required to be portable, and has the defect of tending to be lost.

However, an ejection spring and a reset spring need to work together to execute the quick exchange operation, and the operation tends to go wrong after long-term use, bringing certain inconvenience to users.

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